Instrument Preset, Partial Preset; How Turning The Power On Affects Instrument Settings - HP 8642A Operating Manual

Model 8 6 4 2 A / B Operation
INSTRUMENT PRESET, PARTIAL PRESET
Description Signal Generator settings can be reset by switching the Power from standby to on,
selecting Instrument Preset, or by selecting Partial Preset.
The instrument is turned on by switching t POWER"! from STBY to ON. When it is
turned on, the Signal Generator goes through a sequence of internal checks. If the
instrument encounters no problems, it sets itself to the initialized state that is set up
with Instrument Preset. If any failures occur during the power-up self check,
hardware messages are queued up to be selected with the 1 MSSG1 key. (If the
messages encountered cannot be found in the Operating Messages operating
instruction beginning on page 3-177, refer to the Service Manual.) The power-up self
check takes approxima*ely 20 seconds.
Instrument Preset is selected with 1 INSTR PRESET 1. This function sets the Signal
Generator to the initialized state described on page 3-138.
Partial Preset is selected with PARTIAL ( 1 SHIFT1 I INSTR PRESET ~| ) and enables
you to set the instrument to a known state without losing some frequently used
settings. This function maintains some current instrument settings, turns off others
(while maintaining their last-selected values so they can be selected "on" with the
[ OFF O N I key), and resets other settings to Instrument Preset values. Because Partial
Preset does not reset the entire instrument state, it takes less time than does
Instrument Preset. (For example, Partial Preset may take only a few hundred
milliseconds while Instrument Preset takes approximately two seconds).
Procedures
POWER
How Turning the Power On Affects Instrument Settings
Switching the [ POWER ~1 switch from STBY to ON changes the instrument settings to
those listed for Instrument Preset (refer to "How Instrument Preset Affects Instrument
Settings" on the following page) plus the following:
• HP-IB is set to local mode.
• The Signal Generator is configured to an unaddressed condition.
• The HP-IB address is set to that of the internal switch if RAM memory has been
lost. (RAM memory could be lost, for example, if the battery loses its charge.) (Refer
to HP-IB Address on page 3-8.)
• If RAM memory has been lost, the sequence function is set to a start register of 00
and a stop register of 50.
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